This invention relates to a device for removing or destroying ambient bacteria, viruses, and the like. More particularly, this invention relates to a filtration system for use in portable, hand-held, upright, or canister vacuums, and to vacuum cleaners that incorporate or include such modules therein.
Airborne bacteria and viruses cause infection and disease through nasal inhalation, among other means, and pose a danger if spread accidentally or intentionally in the atmosphere. Likewise, various gasses, for example, such as sarin and cyanide pose an extreme or lethal health threat, if released into a populated civilian or military area. Further, various chemical and biological agents which are applied to or settle on surfaces such as flooring, rugs or carpets, and furniture can be absorbed through the skin or mucous membranes of an individual who comes into contact with such agents. Prior attempts to provide a system which can collect and destroy biological agents, including bacteria and viruses (not limited to those small enough to pass through a HEPA filter), as well as absorb or neutralize chemical agents, including poisonous gasses, liquids or solids, which can be inhaled or absorbed by an individual who comes into contact with one or more such agents, appear to provide an incomplete solution to the hazards posed by exposure to such agents.
U.S. Pat. No. 4,536,914 (Levine) discusses a wet-dry portable vacuum cleaner suitable to clean up both liquid and solid spills. According to the patentee, the cleaner has a blower, a motor, a canister having a nozzle, and a storage chamber beneath the nozzle. The intake port has a liquid deflecting hood extending from an upper portion thereof into the chamber for deflecting any liquid exiting from a posterior port of the nozzle into the chamber, as discussed in the foregoing patent, and its companion, U.S. Pat. No. 4,542,557 (Levine).
U.S. Pat. No. 4,610,048 (Ishihara) provides a hand-held vacuum cleaner having a first section comprising an extendable telescoping opening connected to a second section that comprises a motor, fan handle, and filter. The two sections are joined together by a locking mechanism that provides a snug fit to prevent leaks between the two units. The telescoping opening permits access to areas that might not otherwise be accessible to a hand-held vacuum cleaner.
U.S. Pat. No. 4,577,365 (Yuen) discloses a rechargeable vacuum cleaner that includes a front portion with an intake nozzle, a body portion and a handle portion, with the body portion mounting a motor fan suction unit and a filter, and having outlet apertures therein for air from the motor fan suction unit. The filter includes a disk of flexible filter material sandwiched between two annular members, one of which defines a grid framework over which the disk of flexible filter material is stretched when one of the members is telescopically received within the other of the members with the filter material located therebetween.
U.S. Pat. No. 4,924,548 (Touya) discusses a portable vacuum cleaner for use in both dry and wet operations. It has a main body case housing, a fan motor, intake and discharge openings, and a dust case having an intake portion that is removable from the main body case at the intake opening. It also has a filter housing with a filter covering the intake opening.
Each of the foregoing patents, incorporated herein in its entirety, does not appear to provide a vacuum cleaner or similar appliance that can absorb or destroy chemical or biological contaminants on the surface in a given area.
In a first embodiment, the invention provides a portable or hand-held vacuum cleaner that includes a filtration system or filtration module that can pick up particles and contaminants. It has a first passive stage to collect dust particles, and contaminants over a predetermined size. For example, the passive stage may include a HEPA filter to collect particles above about 0.3xcexc, with or without activated charcoal to absorb odors or noxious gasses. The vacuum cleaner also includes an active stage filter which may include one or more chemical (or biological) agents effective to kill bacteria, viruses, spores, fungi and the like. Preferably, it includes a UV or other radiation source capable of creating ozone from atmospheric oxygen, such that the ozone destroys bacteria viruses and other biological contaminants.
In a second embodiment, the invention provides an upright, canister or backpack (see, e.g., U.S. Pat. No. 6,295,692, incorporated herein by reference) vacuum cleaner which may be used in a home, office, hotel, factory, or other public space. This vacuum cleaner, like the previous embodiment, includes a two stage filtration system or filtration module that can collect debris, particles and most contaminants, as well as an active stage to destroy bacteria or other biological contaminants too fine to trap in the first stage filter.
In yet another embodiment, the invention provides a filtration module, cartridge or insert for a portable, hand-held, upright or canister vacuum cleaner or other appliance, which includes a two stage, passive/active filtration system as mentioned above, and discussed in more detail below.
In still another embodiment, the invention provides a filtration and sanitation module that can be incorporated into another appliance, such as a refrigerator, conventional or microwave oven, dishwasher, or the like, to help kill contaminants on articles placed therein.